Nordic public broadcasters DR and NRK have removed a documentary about Russian espionage from their websites, citing concerns that artificial intelligence (AI) tools might be used to identify anonymous sources featured in the series. The documentary, titled "Skyggekrigen" ("Shadow War"), was produced by four Nordic public channels and explores alleged Russian intelligence activities in Northern Europe. It claims that at least 50 civilian Russian ships may have been used to secretly gather information and investigate buildings suspected of mapping sensitive infrastructure for potential sabotage. The decision to remove the documentary was based on the precautionary principle, aimed at preventing AI from being used to identify individuals who were meant to remain anonymous. According to Frode Frøyland, editor-in-chief of the NRK program Brennpunkt, the documentary was temporarily taken offline after DR informed them of their decision. NRK stated that the documentary had been fully anonymized during its initial release and is currently being prepared to be put back online. Morten Goodwin, a professor of artificial intelligence at the University of Agder, explained that inadequate anonymization can allow AI to identify sources. He noted that AI has become highly effective at removing anonymity from content, especially when the anonymization is not thorough. Goodwin emphasized that media outlets aiming to protect the anonymity of sources must ensure that both the person's face and environment are completely blurred, along with their voice being fully modified. He added that if anonymization is done properly, there is no reason for concern. DR did not immediately respond to requests for comment from AFP. The situation highlights the growing challenges faced by media organizations in balancing the public's right to know with the need to protect the identities of sources who provide sensitive information. As AI technology continues to evolve, the methods used to protect anonymity must also keep pace to remain effective.